Detonator holder

ABSTRACT

An apparatus for holding an explosive charge in place at the outlet of a gas filled chamber. A holding means which may be provided with a plurality of legs, is provided with a receptacle means to accommodate and keep stationary the explosive charge, against the outlet, inside the chamber. Means are provided on the inside surface of the chamber to accommodate the legs, if provided, to assist in keeping the holding means and thus the explosive charge, stationary.

nite i l States tent 1 1 1111 3,859,921 Stephenson Jan. 14, 1975DETONATOR HOLDER 3,208,381 9/1965 Kihlstrom et a]. 102/30 Inventor:Robert L Stephenson, Sterling 3,366,056 1/1968 Thunnell et al 102/30Heights, Mich. FOREIGN PATENTS OR APPLICATIONS [73 Assignee: AlliedChemical Corporation, New 493,667 3/1930 Germany 102/30 York, NY.Primary Examiner-Verlin R. Pendegrass [22,] Flled: 1973 Attorney, Agent,or FirmJonathan Plant [21] Appl. No.: 351,228

Related U.S. ApplicationData [57] APSTRACT [62] Division of Ser. No.162,898, July 15, 1971, Pat. No. apparatus-for holding an explosiveCharge 111 Place 3 74 2 4. at the outlet of a gas filled chamber. Aholding means V which may be provided with a plurality of legs, is pro-[52] US. Cl 102/22, l02/21.8, 102/30 vided with a receptacle means toaccommodate and [51] 1m. (:1. F42b 3/04 p stationary the explosive a gagainst the [58] Field of Search 102/2l.8, 22, 24, 30 let, inside theohamberan are pro ided on the inside surface of the chamber toaccommodate the legs, [56] References Cit d if provided, to assist inkeeping the holding means and UNITED STATES PATENTS thus the explosivecharge, stationary.

3,151,556 10/1964 Karpovich 102/30 2 Claims, 6 Drawing Figures PATEHTEI]JAN 1 M975 SHEEI 10F 2 PATENTED JAN 1 4|975 SHEEI 2 OF 2 FIG. 5

DETONATOR HOLDER This is a division, of application Ser. No. 162,898,filed July 15, 1971, and now US. Pat. No. 3,746,214.

BACKGROUND OF THE DISCLOSURE The instant invention is directed to anapparatus for holding an explosive charge in place. More specifically,the instant invention is directed to an apparatus for holding anexplosive charge in place at the outlet of a gas filled chamber. Stillmore specifically, the instant invention is directed to an apparatus forholding an explosive charge in place at the outlet of a gas filledchamber in communication with an inflatable gas bag.

Problems associated with voluntary restraint systems in motor vehicleshave become more serious in recent years. Specifically, the non-use ofseat belts has resulted in many serious injuries that could have beenprevented had the vehicle occupant been restrained. Thus, much efforthas been expended to design a system that would restrain vehicleoccupants automatically upon collision of the vehicle. The mostpromising of these systems is the inflatable gas bag restraint system.

In all the suggested embodiments of an inflatable gas bag system, meansare provided to supply the gas to the inflatable gas bag. Whether thegas is provided in a compressed gas cylinder, or whether the gas isgenerated by the combustion of a combustible material, or a combinationof the two methods, the gas must be released to the inflatable gas uponimpact or collision of the vehicle. One preferred method to accomplishthis purpose is an explosive charge placed inside the chamber in whichthe gas is stored or generated. The charge is exploded upon impact ofthe vehicle, to rupture the sealing means and release the gas which, inturn, inflates the bag.

In the prior art, this important feature necessary to the successful useof inflatable gas bag assemblies pres ented a difficult problem. Theexplosive charge is usually held to an outlet plug or disc at thedownstream end of the gas chamber by plaster, cement, a rubber moldingcompound or the like. These glue type fasteners are subject to loss ofholding power due to vibrational forces. Since these assemblies aredisposed in motor vehicles the glue type fasteners are subject toconsiderable vibration. As a result, unfastening of explosive chargeshas become a problem which may result in a malfunction in which theinflatable bag fails to inflate upon collision of the vehicle.

SUMMARY OF THE INVENTION Theinstant invention is directed to anexplosive charge holding means assembly which stations the explosivecharge in place at the downstream end of a gas chamber, independent ofthe vibrational forces imposed upon the assembly. In accordance with theinstant invention, an explosive charge holding means in provided, insidethe gas chamber, at the outlet and thereof. The holding means includes abody portion provided with at least one opening to accommodate at leastone explosive charge. The assembly is further povided with wedge meansto keep the assembly stationary inside the gas chamber.

BRIEF DESCRIPTION OF THE DRAWINGS The instant invention may be betterunderstood by reference to the accompanying drawings of which:

FIG. 1 is a perspective view of a preferred embodiment of the holdingmeans of the instant invention;

FIG. 2 is a perspective view of another preferred embodiment of theholding means of the instant invention;

FIG. 3 is a sectional elevation view of the preferred embodimentillustrated in FIG. I shown in a gas chamber;

FIG. 4 is a sectional elevation view of the preferred embodimentillustrated in FIG. 2 disposed in a gas chamber;

FIG. 5 is a perspective view of still another preferred embodiment ofthe holding means of the instant invention; and

FIG. 6 is a sectional elevation view of the embodiment illustrated inFIG. 5 disposed in a gas chamber.

DETAILED DESCRIPTION Turning now to the drawings in detail, in FIG. 1the holding means of the instant invention is generally indicated at 2.The holding means 2, a hold-down assembly, comprises a body membergenerally indicated at 4. In the preferred embodiment illustrated inFIG. 1, the body portion 4 comprises an upper section 3 having an outerdiameter smaller than the outer diameter of a lower section 5. Thedifference in diameter permit the stationing of a flat disc 6,preferably a washer, of the same material as the rest of the assembly2,- about the upper section 3. The disc 6 abuts against the lowersection 5. Such an arrangement provides removability of the disc 6. Thebody member 4 is provided with a uniform opening 9, closed at one end,within the body portion 4. An explosive charge, cylindrical in shape, isdisposed in this opening. A narrow cut 23 is preferably provided in thebody portion to permit a snug fit for the charge without cracking themember.

In the preferred embodiment of FIG. 1 the holddown assembly 2 is itselfheld stationary by wedge means. In this preferred embodiment two wedgemeans are provided. The first wedge means comprises a plurality of legs8 which extend from the body member 4. In this embodiment three legsstationed apart are employed. As will be described below any number oflegs in excess of one may be provided. The legs 8 are flexible so thatthey may be narrowed to fit inside the inner diameter ofa gas chamber.The legs are, thereafter, allowed to spread apart against the insidesurface of the chamber to hold the assembly 2, and the explosion chargedisposed therein, stationary.

The flat circular disc 6 provides a second wedge means. It is removablydisposed over the narrower section 3 of the body portion 4 to furtherassure stability of the assembly 2. The disc 6 is wedged against theinside surface of the chamber to help keep the assembly 2 stationary. Anarrow slit 21 having a length approximately equal to the radius of thedisc 6, may be cut into the disc to again help accommodate the explosivecharge and also assist in wedging of the disc 6 into the inside surfaceof the chamber in which it is disposed.

FIG. 2 illustrates a second preferred embodiment of the holding means ofthe instant invention which is preferred when two explosive charges areemployed. The holding means comprises a hold-down assembly 50 whichincludes a body portion generally indicated at 54. The body portion 54is provided with two openings 53 and 55, closed at one end, toaccommodate two ex plosive charges. In a preferred embodiment theopenings 53 and 55 are cylindrically shaped to accommodate cylindricallyshaped explosive charges. As in the previous embodiment, the bodyportion 54 may be provided with a cut 25 to provide room for expansionof the openings 53 and 55 to permit a snug, stationary fit of theexplosive charge. Unlike the hold-down assembly 2, the outer diameter ofthe body portion 54 is approximately equal to the inside diameter of thegas chamber in which it is disposed. Thus, the outer diameter provides afirst wedge means to prevent movement of the assembly 50. Two smallsized holes 57 and 59 are provided between the bottom of the bodyportion 54 and the closed end of openings 53 and 55 respectively, topermit electrical communication to the charges. A similar opening, toprovide the same function, is included in the assembly 2 at 11.

A second wedge means is provided by a plurality of legs 58 which areconnected to and extend from the body portion 54. In the preferredembodiment illustrated at 50, two legs, disposed 180 apart, areemployed. Again, the legs are flexible, capable of being squeezedtogether and thereafter being released to extend against the insidesurface of the chamber to hold the assembly 50 stationary.

It should be appreciated that various features of the two'preferredembodiments described above may be combined to provide additionalembodiments within the scope of the instant invention. For example, thehold-down assembly 52 may be provided with three or more legs, while theassembly 2 may include only two legs.

It should furthermore be appreciated that although the above descriptioninfers a cylindrical construction to the holding means, portions of theholding means may take other geometric shapes without departing from thescope of the instant invention.

A third preferred embodiment of the instant invention still furthersimplifies the design of the hold-down assembly of the instantinvention. This embodiment is depicted in FIG. 5. The hold-down assemblygenerally indicated at 60 includes a body portion 62 for accommodationof an explosive charge. The body portion 62 includes opening 63 forinsertion of the charge, at one end, and a second smaller opening 64 atthe other end to station the charge while maintaining means forelectrical communication to the charge. A narrow slit 65 is providedalong the length of the body portion 62 to permit wedging of theexplosive charge in the body portion 62 to thus assure a stationary fitof the charge.

The hold-down assembly 60- is also provided with wedge means to engagethe inside surface of a chamber in which it is disposed. In thisembodiment the sole wedge means are provided by a cylindrically shapemember 66 integrally connected to the body portion 62. The outsidediameter of member 66 is approximately the same as that of the insidediameter of the gas chamber in which it is disposed. The cylindricalshaped member 66 is provided with the open slit 65 which continues insingle line along the length of the assembly 60. Again the slit 65 helpsin wedging the explosive charge into the opening provided in the bodyportion 62 and also in wedging the assembly 60 into the gas chamber.

In each preferred embodiment the holding meansis preferably constructedof hard plastic. Alternately, the

holding means may be constructed of a lightweight metal such asaluminum. 7

The holding means depicted in FIG. 1 is shown, in FIG. 3, disposedinside a gas chamber, generally indicated at 10. The assembly 2 is showndisposed adjacent the downstream end of the chamber 10. The chamber 10is closed at this end by a rupture disc 16. The body portion 4 isdisposed adjacent disc 16 with an explosive charge 18 held stationaryinsidethe opening 9 formed in the body portion 4.

The assembly 2 is held stationary in the chamber 10 primarily by theweding effect of the plurality of legs 8 disposed in an indentation 14provided on the inside face of the wall 12 of the chamber 10. Theindentations 14 may comprise a single circular groove provided on theinside surface of the wall 12. Such a single groove has the advantage ofbeing usable with a hold-down assembly with any number of legs.Alternately, a plurality of indentations, of a size sufficient toaccommodate a single leg, and equal in number to the number of legsprovided on the hold-down assembly may be provided.

A second means by which the holding means is held stationary is alsoillustrated in FIG. 3. The flat disc 6 wedges against the inside face ofthe housing 12. In the case of the hold-down assembly 50 the outerdiameter of the body portion 54 wedges the assembly 50 against theinside face of the chamber housing 12.

In FIG. 4 the holding means 50 is shown disposed in the downstream endof the gas chamber 10. As shown, the holding means 50 holding twoexplosive charges 18, is held stationary inside the housing 12. However,certain modifications have been made in this embodiment.

The most obvious modification in the provision for two explosivecharges. To provide for this the body portion 54 is strengthened andwidened. The body portion is provided with an annular taper 56. Thisfeature permits easy disposal of the assembly 50 into the chamber 10,while at the same time providing a wedging effect to keep the assembly50 stationary inside the gas chamber 10. In this regard, it should benoted that the maximum external dimension of the body portion 54 isapproximately equal to the inside diameter of the housing 12.

A second difference relates to the number of legs 58 appended from thebody portion 54. In this embodiment two legs 58 are wedged againstindentations provided in the inside surface of the housing 12. Ofcourse, the number of legs 58 extending from the body portion 54 is amatter of design and may be varied depending on strength and spaceconsiderations.

The embodiment illustrated in FIG. 5 is shown'disposed in the downstreamend of the gas chamber 10. As in the first embodiment the assembly 60 iscapable of holding a single explosive charge 18.

The assembly 60, however, differs from assembly 2, as well as assembly50, in the cylindrical member 66 serves as the sole wedging means tohold the assembly 60 in place inside the gas chamber 10. The use of thecylindrical member 66 replaces the leg members of the other twoembodiments.

In operation, the charge 18 is exploded by a signal communicated to thecharge 18 by a wire 19, disposed through holes 57 and 59, 64 or 11,which communicates an electrical signal from a sensor (not shown). Thesensor initiates the signal to explode the charge 18 upon collision ofthe vehicle in which the gas chamber 10 is disposed. The explosivecharge 18 blows out the rupture disc 16 (as well as breaking apart theassembly 2,50 or 60) permitting gas, stored and/or generated in the gaschamber 10, to flow into a inflatable gas bag (not shown) incommunication with the outlet of the gas chamber 10.

The description of the preferred embodiments of the instant invention,given above, will make apparent other embodiments and modificationswithin the scope and spirit of the instant invention. The scope of theinstant invention, should, thereof, be limited only by the appendedclaims.

What is claimed is:

1. An assembly to hold an explosive charge disposed in a gas chambercomprising modate two explosive charges.

1. An assembly to hold an explosive charge disposed in a gas chambercomprising a body portion provided with at least one opening toaccommodate at least one explosive charge; a first wedge means connectedto said body portion; and a second wedge means comprising a plurality oflegs extending from said body portion, wherein said first wedge meanscomprises the tapered shape of said body portion having a maximum outerdimension approximately equal to the inside diameter of said gaschamber.
 2. An assembly in accordance with claim 1, wherein saidassembly is provided with two openings to accommodate two explosivecharges.